-- 操作的Redis key
local key = KEYS[1]
-- 关注的用户id
local followUserId = ARGV[1]
-- 时间戳
local timestamp = ARGV[2]
-- 过期时间
local expireSeconds = ARGV[3]

redis.call('ZADD', key, timestamp, followUserId)
redis.call('EXPIRE', key, expireSeconds)
return 0
